This detail page shows several photos of the book to show what a first edition looks like.  The images are original photos taken of my personal copy of the first edition book. 

Gambit - Collins (1963):

• This is the Collins Crime Club UK first edition
• The front flap has the price at the bottom (12s 6d net)
• The cover is red cloth with black lettering and a logo on the spine.
• The copyright page says "First Published in Great Britain"
• It also has no further printings noted and has the copyright symbol (© Rex Stout, 1962) on the top line of the three lines at the bottom of the page